I have this same problem just seemingly random happen. I am being asked to update avast, and I'm too busy for a reboot, so I know it's not caused by an update. All of a sudden the folders I have in the excluded settings, (both File System shield and normal scan settings), are being ignored. It used to work but now (randomly?) it does not. I checked the settings and the folders in question are still listed there, but being completely ignored by the program. Now Avast deletes my files whenever i use them, saying virus (which its not even BTW), and deleting my files. NOT cool... I've used Avast since a company I used to work for thought it was decent enough... (5 Years now), and if this problem cant be resolved I'll be switching to something else.
I don't use steam either BTW...
PLEASE HELP